Navigation Links
Stronger corn? Take it off steroids, make it all female
Date:11/30/2011

WEST LAFAYETTE, Ind. - A Purdue University researcher has taken corn off steroids and found that the results might lead to improvements in that and other crops.

Burkhard Schulz, an assistant professor of horticulture and landscape architecture, wanted to understand the relationship between natural brassinosteroids - a natural plant steroid hormone - and plant architecture, specifically plant height. Schulz said corn could benefit by becoming shorter and sturdier, but the mechanisms that control those traits are not completely understood.

"It is essential to change the architecture of plants to minimize how much land we need to produce food and fuels," said Schulz, whose findings are published in the early online version of the Proceedings of the National Academy of Sciences. "If you can find a natural mutation or mechanism that gives you what you need, you are much better off than using transgenic techniques that could be difficult to get approval for."

Schulz found that when maize loses the ability to produce brassinosteroids, it becomes a dwarf, as he suspected. But another feature caught him off guard: The plants without the naturally occurring steroids could not make male organs - they had kernels where the tassels should be.

That could be a cost-saving discovery for the seed industry. Hybrid seed producers must painstakingly remove the male pollen-producing tassels from each plant so that they do not pollinate themselves. Schulz said maize plants that produce only female organs would eliminate the detasseling step.

"This would be the perfect mutation for hybrid seed production," Schulz said. "There is no way these plants could produce pollen because they do not have male flowers."

Schulz used a multistep process to determine brassinosteroids' role in height and, later, sex determination. He wanted to ensure that light and the addition of gibberelic acid, a hormone that promotes cell growth and elongation, would not eliminate the dwarfism.

Schulz gathered known mutants of maize with short mesocotyls, the first node on a corn stalk. He suspected that even dwarf plants that produced brassinosteroids would have elongated mesocotyls if grown in the dark as they stretched for light, a trait typical of all brassinosteroid mutants. He also added gibberellic acid to the plants to ensure that a deficiency of that hormone was not causing the dwarfism.

The dwarf plants that did not grow in the dark or with the addition of the gibberellic acid were compared to regular maize plants that had been dwarfed by subjecting them to a chemical that disrupts the creation of brassinosteroids. Both exhibited short stalks with twisted leaves and showed the feminization of the male tassel flower.

Schulz then used information that was already known from the research plant Arabidopsis about genes that control brassinosteroid production. He found the same genes in the maize genome.

In the dwarf maize plants, those genes were mutated, disrupting the biosynthesis of the steroids. A chemical analysis showed that the compounds produced along the pathway of gene to steroid were greatly diminished in the maize dwarfs. Cloning of the gene revealed that an enzyme of the brassinosteroid pathway was defective in the mutant plants. A related enzyme in humans has been reported as essential for the production of the sex steroid hormone testosterone. Mutations in this enzyme in humans also resulted in feminization.

While Schulz expected brassinosteroids to affect plant height, he said he did not expect those steroids to affect sex determination.

"We don't know if this is a special case for corn or if this is generally the same in other plants," he said. "If it is the same in other plants, it should be useful for creating plants or trees in which you want only males or females."

Gurmukh Johal, a professor of botany and plant pathology and collaborator on the research, identified the mutant used in the research, nana plant1, years ago. He said better understanding the steroid-production pathways could be important to strengthening maize plants and increasing yields.

"Maize produces too much pollen and it actually wastes a lot of energy on that," Johal said. "This implies that by using this gene or the pathway it controls, we could manipulate the plants to improve their quality."

Schulz said he would look at other plants, such as sorghum, to determine if the same genes and pathways control sex determination and height.


'/>"/>
Contact: Brian Wallheimer
bwallhei@purdue.edu
765-496-2050
Purdue University
Source:Eurekalert  

Related biology news :

1. Groundbreaking discovery may lead to stronger antibiotics
2. As sticky as a gecko... but 10 times stronger!
3. New type of vaccines deliver stronger and faster immune response
4. Immunity stronger at night than during day
5. Stronger coastal winds due to climate change may have far-reaching effects
6. AJCN study shows moderate alcohol consumption related to stronger bones
7. Information warfare in the 21st century: Ideas are sometimes stronger than bombs
8. As good as it gets: Octogenarian muscles dont get stronger with exercise
9. Scientists explain how death receptors designed to kill our cells may make them stronger
10. City of Winter Park Looks to DigitalPersona Software for Stronger Security and CJIS Compliance
11. Study links 1976 swine flu shot to stronger immune response to 21st century pandemic flu
Post Your Comments:
*Name:
*Comment:
*Email:
Related Image:
Stronger corn? Take it off steroids, make it all female
(Date:4/4/2017)...   EyeLock LLC , a leader of iris-based ... Patent and Trademark Office (USPTO) has issued U.S. Patent ... an iris image with a face image acquired in ... 45 th issued patent. "The ... the multi-modal biometric capabilities that have recently come to ...
(Date:3/30/2017)... 2017 Trends, opportunities and forecast in this ... technology (fingerprint, AFIS, iris recognition, facial recognition, hand geometry, ... end use industry (government and law enforcement, commercial and ... and others), and by region ( North America ... Asia Pacific , and the Rest of the ...
(Date:3/24/2017)... March 24, 2017 The Controller General of Immigration ... Abdulla Algeen have received the prestigious international IAIR Award for ... Continue Reading ... ... Deputy Controller Abdulla Algeen (small picture on the right) have received the ...
Breaking Biology News(10 mins):
(Date:10/11/2017)... ... October 11, 2017 , ... ... Andi Purple announced Dr. Suneel I. Sheikh, the co-founder, CEO and chief research ... Inc. has been selected for membership in ARCS Alumni Hall of Fame ...
(Date:10/11/2017)... ... October 11, 2017 , ... ComplianceOnline’s Medical Device Summit is back for its ... 2018 in San Francisco, CA. The Summit brings together current and former FDA office ... directors and government officials from around the world to address key issues in device ...
(Date:10/11/2017)... HILLS, Calif. , Oct. 11, 2017  SkylineDx today ... (ICR) and University of Leeds ... risk-stratify patients with multiple myeloma (MM), in a multi-centric Phase ... University of Leeds is the sponsor ... and ICR will perform the testing services to include high-risk ...
(Date:10/11/2017)... (PRWEB) , ... October 11, 2017 , ... ... Administration (FDA) has granted orphan drug designation to SBT-100, its novel anti-STAT3 (Signal ... the treatment of osteosarcoma. SBT-100 is able to cross the cell membrane and ...
Breaking Biology Technology: